On (20 Apr 97) Darin McBride wrote to Danial Gibson...
[ talking about numbering messages sent via a mailslot ]
 DM> Of course, you could use four bytes - you'd have to reach 4.1 billion
 DM> for it to overflow.  How often are these messages passed back and
 DM> forth?  Perhaps 4 billion may not "theoretically" be enough.
Perhaps.  Assuming you're sending the messages over Ethernet, that each
message is small enough to consume only one minimum size Ethernet packet
(no more than 53 bytes of data), and that no other data is transmitted
over the LAN in that time we use up the packet numbers as fast as
possible, 4 bytes only gives us enough to run continuously for over 69
centuries before we have to repeat a number.
Worse yet, if we happen to be using FDDI instead of Ethernet, we could
actually use up the numbers only about 5 centuries of continuous use.
This could certainly lead to different packets with the same number.
The last time I had a tight deadline to meet, I'm pretty sure copying
one file from one machine to another took at least 12 or 14 centuries.
    Later,
    Jerry.
... The Universe is a figment of its own imagination.
--- PPoint 1.90
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